Most of the material contained within these pages was created by Akiyoshi
Kitaoka and is not copyright-free. If you wish to use any of the material
for research purposes, personal purposes, or educational purposes, you
may do so only if you include a citation. To cite my work, use my name,
my site address, the title of my book, or the titles of my papers. For
commercial or professional use, please contact the publisher "Kanzen"* who manages my published material. If you are a journalist and wish to
use my material, only I can grant you permission to use my work.

*For the response from Kanzen, please wait about one week because it takes
time to translate languages in the company.

For commercial customers, we can send image files in Adobe Illustrator
format (ver. 8 or higher) or in bitmap (jpeg) format of any size. We also
have files available in PDF, CorelDRAW, MS-Word, and related formats. <November
18, 2004>

I have received a number of requests asking for permission to upload some of my illusion designs to webpages and I have granted such permission on an individual basis. Hereafter, I grant permission to upload to your webpage up to three (3) images if your webpage is to discuss the science of illusion or vision, is not a commercial site, and does not contain indecent, obscene, or illegal content. Religious or political sites would be declined. The sites that I cannot reach would be declined, either. My name and the address of my webpage (a link is OK) should be cited. Moreover, a cautionary message or warning like "These images might make observers feel sick" is necessary if they are anomalous motion illusions. Please withdraw my works from the sites if they do not satisfy the conditions shown above. <September 24, 2003; updated June 23, 2005>

The "Download" page was closed because of too much illegal use of my material. Please do not use them for commercial purpose without permission. For educational or research use of my high quality material, please send your request to me. I am sorry that original vector files or large bitmap files will not be provided for personal use. <May 28, 2004>

If you send me an e-mail, please do not attach any files because I might
erroneously delete the e-mail thinking that a virus is hidden in the file.
<August 30, 2004; updated May 8, 2011>

If you sent me an e-mail but have not heard from me within a week, I might
possibly remove it in error. Then, please send it to me again with a clear
title, e.g. "about illusion".<June 11, 2006>

It is my pleasure to grant permission for the use of my illusion material
for papers, articles, or books if they are for educational or research
purposes. In this case, I would like the authors to request permission.
Requests from publishers or other agencies are not welcome. Requests for
written permission are not welcome either, because it takes time to check,
sign, and send it back, though I will do so if it is absolutely necessary.
Of course, I give written permission if it is a commercial gift. <September
16, 2004>

Links to my website are welcome. Please link to this top page so that we
can avoid overworking the Ritsumeikan University servers. <October 4,
2004>

Do not worry or become upset if you cannot see the illusions. I must confess
that even I do not see some illusions. For instance, the Ponzo illusion, if the image is the upper-converging version, is difficult to see. <October
16, 2004>

Thanks to David <November 29, 2004>

Announcement: A website "Test online the level of stress a person can handle using
stress pictures: are they animated, moving?" abuses three of my illusion
works as well as claims an unscientific idea. To my knowledge, stress has
nothing to do with visual illusion. <April 25, 2011>